Ng-switch in modal has a weird animation applied

I have created a codepen to illustrate. Basically an animation is being applied to the ng-switch div that i created inside a modal page

http://cdpn.io/CvlcK

on that page, press switch. a new button that reads “go back” should be visible. please note the weird animation to the top that is being applied. I would like to remove it and/or at least choose which one i would like.

I have modified the sample code to illustrate that outside the modal window, this animation does not occur